Improvement in sash-holders



dimi @mw Letters Patent No. 112,985, dated March 21, 1871.

iEdPRVEMENT IN SASHHOLDERS.

' The Schedule referred te in these Letters Patent and making part ofthe same.

I, ALEXANDER TnoMsoN, of Champaign Uity, in the county of Champaign andState oi' illinois, have invented a certain Friction Window-Lock, lofwhich the following is a speciiication.

bjeot of the Invention.

The object of the invention is to -make a strong and' efcient automaticlock, and to hold the window down or in any other position by means offriction, in such n manner as not to deface the jamb-ofthe window.

Description of the Accompanying Drawing.'

Figure 1 is a perspective view.

` Figure 2 is av vertical section.

General Description. A'is a key having two inclined faces, i) and t',the

inclination being such that the tangents of the angles,v

which the faces-make with jamb D, shall be less than the coeiiicient offriction; or, in other'words, that the roller B will roll onto b or i,as the casey may be, in-v stead of slipping on jamb D.

The side of key A, which bears against jamb D, is not a perfect plane,but. is bent at c, as shown in iig. 2, this being done to prevent rollerB from breaking it atc. v

The surface of key A, which bears against jamb D, is of sufficient areafrom c to either end as to prevent it from defacing jamb D.

O is a case which is fastened to sash E by means of three screws, e, Z,and f, inside of which is placed the roller B, through which the screw fpasses, forming a bearing for roller B.

Boiler B should be placed sufficiently close to key A as to nllo'w key Abut little upward or downward motion, which may be regulated by placingprojection I almost in contact with jamb D.

The key A is held in its place by the projection I on case C, l

Oase G may be dispensed with, and roller B heldin position by one screwof sufficient strength, and key A heldin place by means of a fiange onroller B instead of the projection I.

This lock operates in the following manner iii/'hen the window is downand force applied to raise sash E, roller B moves up the inclined'faceb, causing ypressure upon jamb D and also upon the jamb at the oppositeside ofthe window, which causes friction betw'een thev sash and theopposite jamb, and also between key A and jamb D, thus `preventing thesash,

from rising. By raising key A so that the inclined face i comes incontact with roller B, and holding it in this position, sash E is freeto move upward. After sash E has been raised to the desired height,rbystill keeping the facci in contact with roller B, and releasing the holdupon sash E, the force of gravity causes roller B to press upon theinclined face-i, causing friction between the opposite side of the sashand the opposite jamb, also causing'friction between key A and jamb D,thus preventing the sash from passing down. 12o let the window down,raise the sash .sufficient to free key A, which drops, bringing theinclined face b in contact with roller B, the force of gravity holdingit in this position, thus allowing sash E to. move down freely, roller Bstill being in contact with the inclined face b.- The sash is locked, asbefore described, thus making it an automatic lock.

Claim.

- I claim- The combination of the double-beveled key A, the case Gholding the key, with its ange, and containing a roller B, all arrangedas set forth. v

ALEXANDER THOMSGN.

Witnesses:

R. E. Moolen, d. B. WATKrNs.

